An Optimal Au Grating Structure for Light Absorption in Amorphous Silicon Thin Film Solar Cell

Plasmonics - Effect of different gold (Au) grating structures on light absorption in solar cell is investigated by finite elemental analysis using COMSOL multiphysics-RF module. The geometry of the...     

A conserved GH17 glycosyl hydrolase from plant pathogenic Dothideomycetes releases a DAMP causing cell death in tomato

To facilitate infection, pathogens deploy a plethora of effectors to suppress basal host immunity induced by exogenous microbe-associated or endogenous damage-associated molecular patterns (DAMPs). In this study, we have characterized family 17 glycosyl hydrolases of the tomato pathogen Cladosporium fulvum (CfGH17) and studied their role in infection. Heterologous expression of CfGH17-1 to 5 by potato virus X in different tomato cultivars showed that CfGH17-1 and CfGH17-5 enzymes induce cell death in Cf-0, Cf-1 and Cf-5 but not in Cf-Ecp3 tomato cultivars or tobacco. Moreover, CfGH17-1 orthologues from other phytopathogens, including Dothistroma septosporum and Mycosphaerella fijiensis, also trigger cell death in tomato. CfGH17-1 and CfGH17-5 are predicted to be β-1,3-glucanases and their enzymatic activity is required for the induction of cell death. CfGH17-1 hydrolyses laminarin, a linear 1,3-β-glucan with 1,6-β linkages. CfGH17-1 expression is down-regulated during the biotrophic phase of infection and up-regulated during the necrotrophic phase. Deletion of CfGH17-1 in C. fulvum did not reduce virulence on tomato, while constitutive expression of CfGH17-1 decreased virulence, suggesting that abundant presence of CfGH17-1 during biotrophic growth may release a DAMP that activates plant defence responses. Under natural conditions CfGH17-1 is suggested to play a role during saprophytic growth when the fungus thrives on dead host tissue, which is in line with its high levels of expression at late stages of infection when host tissues have become necrotic. We suggest that CfGH17-1 releases a DAMP from the host cell wall that is recognized by a yet unknown host plant receptor.     

Modifying bio-catalytic properties of enzymes for efficient biocatalysis: a review from immobilization strategies viewpoint

Enzyme-based catalysis has become one of the most important disciplines in organic synthesis and plays a noteworthy role in the establishment of many chemical industries, e.g. fine chemicals, food or energy, textiles, agricultural, cosmeceutical, medicinal and pharmaceutical industries. However, pristine enzymes fail to demonstrate requisite functionalities for an industrial setting where extremely specific and stable catalysts are required. Immobilization enhances the catalytic stability and activity of enzymes and trims the overall cost burden of the enzyme. Therefore, it widely endeavours for proficient, sustainable, and environmentally responsive catalytic processes. Amongst several immobilization strategies, e.g. (1) supports-assisted, i.e. physical or covalent coupling and (2) supports-free techniques, i.e. cross-linked enzyme crystals (CLECs) or aggregates are the most promising ones and widely pursued for enzyme immobilization purposes. This perspective review focuses on up-to-date developments in the area of enzyme immobilization and presents their potentialities to upgrade and/or modify enzyme properties. Both types of immobilization strategies, i.e. supports-assisted and supports-free techniques are discussed with particular reference to CLECs or aggregates and protein-coated microcrystals. Also, several useful traits achieved after immobilization are also discussed in the second half of the review.     

Cortical State Fluctuations across Layers of V1 during Visual Spatial Perception

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Music of metagenomics—a review of its applications,analysis pipeline,and associated tools

Functional & Integrative Genomics - This humble effort highlights the intricate details of metagenomics in a simple, poetic, and rhythmic way. The paper enforces the significance of the...     

Resolving the pathogenicity factors of a novel opportunistic fungus Schizophyllum commune at molecular level

Molecular Biology Reports - Schizophyllum commune is a well-known mushroom forming fungi which is an edible one due to its nutritive value. It exhibits a special wood degrading mechanism to grow in...     

Moleculer dynamics simulaiton revealed reciever domain of Acinetobacter baumannii BfmR enzyme as the hot spot for future antibiotics designing

Acinetobacter baumannii is an alarming nosocomial pathogen that is resistant to multiple drugs. The pathogen is forefront of scientific attention because of high mortality and morbidity found for its complications in the past decade. As a consequence, identification of novel drug candidates and subsequent designing of novel chemical scaffolds is an imperative need of time. In the present study, we used a recently reported structure of BfmR enzyme and performed structure based virtual screening, MD simulation and binding free energies calculations. MD simulation revealed a profound movement of the best-characterized inhibitor towards the α4-β5-α5 face of the enzyme receiver domain, thus indicating its high affinity for this site compared to phosphorylation. Furthermore, it was observed that the enzyme and enzyme-inhibitor complex have high structure stability with mean RMSD of 1.2 and 1.1 Å, respectively. Binding free energy calculations for the complex unraveled high stability with MMGBSA score of ?26.21?kcal/mol and MMPBSA score of ?1.47?kcal/mol. Van der Waal energy was found highly favorable with value of ?30.25?kcal/mol and dominated significantly the overall binding energy. Furthermore, a novel WaterSwap assay was used to circumvent the limitations of MMGB/PBSA that complements the inhibitor affinity for enzyme active pocket as depicted by the low convergence of Bennett, TI and FEP algorithms. Results yielded from this study will not only give insight into the phenomena of inhibitor movement towards the enzyme receiver domain, but will also provide a useful baseline for designing derivatives with improved biological and pharmacokinetics profiles.

Communicated by Ramaswamy H. Sarma     

Removal of Fe(II) ions from aqueous solution by Calabrian pine bark wastes

The ability of Calabrian pine bark wastes (Pinus brutia Ten) for the removal of Fe(II) ions from aqueous solution at different concentrations and temperatures at a fixed pH was investigated. While the amounts of Fe(II) ions adsorbed onto the bark increased with increasing concentration, it increased slightly with increasing the temperature. Kinetics studies showed that adsorption process followed the first-order kinetic model as well as intra-particle diffusion kinetics. Adsorption isotherm followed both Langmuir and Freundlich models. And it was determined that the adsorption was favorable from a dimensionless factor, R(L). Furthermore, the thermodynamic parameters demonstrated that the removal of Fe(II) by the bark was a physical process.     

Mutagenesis of subunit N of the Escherichia coli complex I. Identification of the initiation codon and the sensitivity of mutants to decylubiquinone

The last gene in the nuo operon of Escherichia coli, nuoN, encodes a membrane-bound subunit of Complex I (NADH:ubiquinone oxidoreductase). In this report, the gene for subunit N was disrupted by a 163 bp deletion in the chromosome, resulting in the loss of Complex I function, as measured by deamino-NADH oxidase activity. This activity could be recovered after transformation of the mutant strain by a plasmid that contains the previously identified nuoN gene and the upstream intergenic region between nuoM and nuoN. Mutagenesis of the first ATG downstream of nuoM led to a loss of function, indicating that this is the likely initiation codon for nuoN, and predicting a protein of 485 amino acids and 52 044 Da. Thirty site-specific mutations in nuoN at 19 different positions were constructed in a vector that expresses the full-length subunit N with both an octahistidine tag and an HA epitope tag at the carboxyl terminus. Highly conserved charged and aromatic residues were selected for mutagenesis, as well as a substitution that occurs as a secondary mutation in Leber's hereditary optic neuropathy (LHON). Membranes from the mutant strains were tested for production of subunit N by immunoblots and for NADH-linked activities. Mutants with substitutions at six different positions (K158, K217, H224, K247, Y300, and K395) had rates of deamino-NADH oxidase activity that were no more than 50% of that of the wild type and had reduced rates of proton translocation. These mutants also showed enhanced inhibition by decylubiquinone, indicating that subunit N interacts with quinones. The mutation associated with LHON, G391S, had little effect on these functions.     

Dedicated Roles of Plastid Transketolases during the Early Onset of Isoprenoid Biogenesis in Pepper Fruits

Isopentenyl diphosphate (IPP), which is produced from mevalonic acid or other nonmevalonic substrates, is the universal precursor of isoprenoids in nature. Despite the presence of several isoprenoid compounds in plastids, enzymes of the mevalonate pathway leading to IPP formation have never been isolated or identified to our knowledge. We now describe the characterization of two pepper (Capsicum annuum L.) cDNAs, CapTKT1 and CapTKT2, that encode transketolases having distinct and dedicated specificities. CapTKT1 is primarily involved in plastidial pentose phosphate and glycolytic cycle integration, whereas CapTKT2 initiates the synthesis of isoprenoids in plastids via the nonmevalonic acid pathway. From pyruvate and glyceraldehyde-3-phosphate, CapTKT2 catalyzes the formation of 1-deoxy-xylulose-5-phosphate, the IPP precursor. CapTKT1 is almost constitutively expressed during the chloroplast-to-chromoplast transition, whereas CapTKT2 is overexpressed during this period, probably to furnish the IPP necessary for increased carotenoid biosynthesis. Because deoxy-xylulose phosphate is shared by the plastid pathways of isoprenoid, thiamine (vitamin B₁), and pyridoxine (vitamin B₆) biosynthesis, our results may explain why albino phenotypes usually occur in thiamine-deficient plants.